防腐与耐磨双重功能铝基亚稳态复合涂层成形机制与性能

Based on the materials preparation and formation integration idea, a type of Al-based amorphous and nanocrystalline composite coating with double functions of corrosion and wear resistance was prepared by automatic arc spraying cored wire process, which was used to protect marine steel structures from corrosion and wear. It is a new production technology of the Al-based amorphous alloy. And it can provide a reliable protective material for the surface protection and maintenance and remanufacturing of marine steel structures. Through researching on the spraying and depositing process of molten droplets during the spraying, the heat and mass transfer basis rule in the formation process of Al-based amorphous and nanocrystallilne composite coating will be revealed. Through researching on the microstructure of the coating and the law of thermodynamics and kinetics in the preparation process, the formation mechanism of amorphous and nanocrystalline phases and anti-oxdation mechanism will be investigated. Through researching on the failure behaviors of corrosion and wear of the coating, the failure mechanisms of corrosion and wear of the coating will also be investigated. The mapping relationship of material design and preparation process and microstructure and properties can be bulit for the preparation of the composite coating. The new type of Al-Ni-Mm-Co amorphous and nanocrystalline composite coating has expected performances as shown below, the bond strength between the coating and steel with more than 40 MPa, the amorphous volume fraction with more than 30%, the porosity with less than 1%, the hardness with more than HV350, the properties of anti-corrosion and wear resistance of the Al-based amorphous and nanocrystalline coatings improved more than 3 times as compared to the conventional Al coatings.

针对海洋钢结构腐蚀与磨损防护问题，基于材料制备与成形一体化思路，采用自动化高速电弧喷涂技术制备具有长效防腐与高效耐磨双重功能的铝基非晶纳米晶复合涂层，拓展铝基块体非晶材料制备技术，为钢结构件表面防护、维修与再制造提供可靠的防护涂层材料支撑。研究喷涂过程中熔融粒子飞行与沉积动态过程，揭示铝基非晶纳米晶涂层形成过程中传热传质基本规律；研究涂层微观组织结构以及涂层制备过程中热力学与动力学规律，探讨涂层中非晶相、纳米晶相形成机理及抗氧化机理；研究涂层动态腐蚀和磨损失效行为，揭示涂层动态防腐与耐磨的协同机理；建立铝基非晶纳米晶涂层制备过程中"材料设计与制备工艺-组织结构-防腐与耐磨双重功能"之间的映射关系。新型Al-Ni-Mm-Co系非晶纳米晶涂层的预期性能指标为：与钢基体结合强度大于40MPa，非晶含量大于30%，孔隙率小于1%，硬度大于HV350，涂层防腐、耐磨性能较传统Al涂层提高3倍以上。

针对海洋钢结构材料苛刻工况环境下对防腐与耐磨双重要求的技术问题，采用高速电弧喷涂技术研发了高非晶含量、兼具防腐与耐磨双重功效的Al-Ni-Zr(-Cr)非晶纳米晶复合涂层，系统研究了涂层成形特征、微观结构和防腐耐磨综合性能等，为海洋钢结构装备表面防护提供了材料支撑和理论依据。自主创新研制了两种用于制备铝基非晶纳米晶复合涂层的粉芯丝材；通过试验获得了最佳喷涂工艺参数：喷涂电流为140A，喷涂电压为34V，喷涂距离为200mm，喷枪移动速度为300m/s，空气压力为0.7MPa；分析结果显示，Al-Ni-Zr和Al-Ni-Zr-Cr两种涂层均由非晶、纳米晶和氧化相复合组成，非晶含量（体积分数）分别为66.7%和71.7%，涂层孔隙率分别为0.8%和0.7%，平均含氧量（原子分数）分别为3.17%和3.16%，平均显微硬度分别为HV364和HV379，与基体间结合强度分别为40.8MPa和42.7MPa；研究了铝基非晶纳米晶复合涂层的宏观和微区耐腐蚀性能，发现了涂层自腐蚀电流密度比纯铝涂层降低了1~2个数量级，揭示了涂层微区腐蚀先后顺序依次为：纯铝相、氧化相和非晶区，并分析了涂层的腐蚀失效机制；研究了铝基非晶纳米晶复合涂层在不同条件下的耐磨损性能：干摩擦条件下涂层磨损体积为纯铝涂层的1/10，磨损形式以氧化磨损和剥层磨损为主，伴有轻微磨粒磨损；腐蚀介质全浸条件下涂层磨损体积为纯铝涂层的4/100，磨损形式以磨粒磨损和剥层磨损为主；极化条件下，涂层受摩擦与腐蚀交互作用影响较小，其磨损体积约为纯铝涂层的4/100，其中Al-Ni-Zr-Cr非晶纳米晶复合涂层表现出最佳耐摩擦腐蚀性能。以上技术指标均满足项目预期目标。项目培养博士后1名、博士生1名和硕士生3名；发表论文19篇（SCI检索4篇、EI检索8篇）；发明专利授权2项、受理5项；出版相关著作3部；获军队科技进步一等奖1项。